This invention relates generally to recording media, and, more particularly, to the formatting of recording media.
In the case of optical tape, which is typically hundreds of meters long, it is a necessity that each track will have an identifiable track number and that each block of data along the track will have a block number, both of which are inscribed on the tape during the formatting process, so that this information can be retrieved reliably when the tape is used later for recording and/or reading of user data.
It is therefore a need to provide a method that adds both track number information and block number information to the formatted pattern in such a manner that its primary functionality, which is to provide reliable tracking position error information, is not disturbed. It is a further need to be able to add this information during the same formatting operation, so that a one-step process is maintained without requiring a separate formatting step.
In summary there is a need for a simple method to modulate track & block number information onto the servomark pattern that satisfies both the need for efficient formatting during tape manufacturing as well as the need for a reliable positioning grid, used during recording or reading of user data.